Wigs are made by two kinds of manufacturing methods, hand-made and machine-made.
A hand-made wig is made by tying the hairs in a net, giving it the particular advantage of looking like natural human hair.
However, it is very hard to mass produce hand-made wigs in view of the fact that great number of working hours are spent in tying the hairs in a net by hand one by one. A machine-made wig has the advantage that it can be mass-produced through a series of manufacturing processes though the quality is not equal to that of a hand-made wig.
U.S. Pat. No. 3,910,291 discloses such machine-made wigs.
The manufacturing process of such machine-made wigs is shown in the accompanying Figures, in which hairs(1) are cut into a predetermined length(see FIG. 1A) and sewn by a sewing machine forming a first pair of double stitch lines(3)(see FIG. 1B). Then, one side of the stitched hairs(1) is folded over on top of the other side along the centerline between the first pair of double stitch lines(2)(see FIG. 1C). The folded hairs(1) are sewn with a second single stitch line(3)(see FIG. 1D). Thereafter, the first double line section is folded over the second single stitch line section(see FIG. 1E). The folded hair(FIG. 1E) is sewn with a third single stitch line(4) (see FIG. 1F).
Wigs(7) as shown in FIG. 3 are made of the hairs(FIG. 2) each of which includes three times sewn weft(5) coated with urethane adhesive. To provide a finished wig(7), each hair(FIG. 2) arranged in the shape of head is sewn with a fourth single stitch(10) on a head cap(8) which comprises an end lace to which a net(8a), lace(8b) and a stretchy band(8c) are connected(see FIG. 3).
To sew the hair(FIG. 2) on the head cap(8) in a predetermined regular interval the head cap(8) is pre-affixed to a head shaped P.V.A.(Poly Vinyl Alcohol) film sheet so that the shape of the head cap(8) itself can be maintained. Thereafter, a wig is finished by sewing the hair(FIG. 2) one by one. The hairs(FIG. 2) of such a conventional wig(7) has a relatively wide weft(5) with three times stitched lines(2)(3)(4).
That is, the hair(FIG. 2) has a relatively wide root. With the weft(5), when the hairs(FIG. 2) are curled, the curled area is formed not adjacent to, but remote from the weft(5) which is the root. Therefore, the curls are not movable in any direction so that the shape of the wigs will not be changed readily. Furthermore, the root of each hair(FIG. 2) becomes flat and wide, making the section which is adjacent to the root stiff.
Therefore, the curled sections extend only in the sewn direction and the combing of the hairs(FIG. 2) in other directions is not readily achieved.
This wide weft(5), when worn on the head, contacts flatly with the scalp(see FIG. 4), exerting pressure on the head. In addition, contacting the scalp by thick wefts(5) and stitch lines(10) cause pain to the scalp. Therefore, the conventional wig has a problem that the wearer cannot wear the wig for a long time.